feat(widgets): pricing/FAQ/stats + forum topic list and bbs sidebars

Add zibll produck widgets (pricing plans, FAQ, stats), forum topic
lists, register bbs_* sidebar zones, and wire plate/topic/home/compose
templates to render those widget areas.

templates/forum/forum-topic.php

@@ -412,6 +412,11 @@ $comments_enabled = !empty($permissions['can_reply']);
                     </div>
                 </div>
             </section>
+            <?php if (is_active_sidebar('bbs_posts_sidebar')) : ?>
+            <div class="aksrt-forum-widget-zone">
+                <?php dynamic_sidebar('bbs_posts_sidebar'); ?>
+            </div>
+            <?php endif; ?>
         </aside>
 
         <div class="aksrt-forum-report-modal" id="aksrt-report-modal" hidden>